Vehicle bench seats, in particular the bench seat of a passenger car, are mostly intended for use by up to three passengers although the middle location often remains unoccupied. For the comfort of the passengers sitting in the outer locations, it is customary to provide a middle arm rest which may be aligned substantially parallel to the upholstered seat surface and in said position often rests on the latter. When the middle location is also occupied, the arm rest may be swivelled into a substantially vertical position, in which it is disposed in a recess of the back rest of the bench seat, resulting in a substantially flat back rest and also allowing a passenger to sit comfortably in the middle of the bench. The arm rest is therefore preferably upholstered on all sides.
To guarantee adequate safety also at the middle location in the event of an accident, a head rest at the top edge of the back rest is required. On the other hand, the head rest obstructs the rear field of vision of the driver and is preferably removable when the middle location is unoccupied. It was therefore proposed in publication EP 0 604 375 to form or attach the head rest onto the front end of the middle arm rest. In such a manner, in the vertical position of the arm rest the head rest projects above the top edge of the back rest and is therefore in a suitable position to protect the passenger. When the middle location is unoccupied, however, the head rest is folded down with the arm rest towards the seat surface and therefore does not obstruct the field of vision of the driver. To achieve an adaptation to the height of the occupant, it is known for the head rest to be extendable out of the arm rest or--in the case of an integral style of construction--displaceable up and down with the arm rest when in the vertical position.
It is moreover customary in many cases for a middle arm rest to be used as a storage compartment or provided with areas where articles may be placed or deposited. In particular, cup and drinks can holders, ashtrays or oddments trays are often fastened to the front end of the arm rest. When not in use, they may be inserted into the arm rest to eliminate risks of injury and avoid clutter. When the front-end region of the middle arm rest is used as a head rest, however, such prior art devices are not usable because the padding of the head rest almost totally takes up the volume of the arm rest required for accommodation.